Biology Questions

Which of the following statements accurately describes the differences between DNA replication in prokaryotes and DNA replication in eukaryotes Prokaryotes produce Okazaki fragments during DNA replication but eukaryotes do not Prokaryotic chromosomes have a single origin of replication whereas eukaryotic chromosomes have many The rate of elongation during DNA replication is slower in prokaryotes than in eukaryotes Prokaryotic chromosomes have histones whereas eukaryotic chromosomes do not

The receptors for steroid hormones are located inside the cell instead of the membrane surface like most other signal receptors How do steroids gain access to their receptors Steroid hormones are lipid soluble so they can readily diffuse through the lipid bilayer of the cell membrane Both steroid hormones and their receptors are produced by the same cells O Steroid hormones first bind to a steroid activator and this complex is transported across the cell membrane by a steroid transport protein Steroid hormone receptors undergo conformational changes that relocate them on the membrane surface

What does it mean to say that a signal is transduced O The signal is amplified such that even one signal mol cule evokes a large response O The physical form of the signal changes as it passes from the cell membrane to the ultimate intracellular target The signal enters the cell directly and binds to a receptor inside The signal triggers a sequence of phosphorylation events inside the cell

Which of the following processes would allow the detection of alternative splicing of transcripts from a given gene Compare the sequences of different mRNAs made from the given gene Compare the sequences of different primary transcripts made from the given gene Measure the relative rates of transcription of the given gene compared to that of a gene known to be constitutively spliced Compare the DNA sequence of the given gene to that of a similar gene in a related organism

Under what conditions does the trp repressor block transcription of the trp operon when the repressor is not bound to tryptophan when the repressor is not bound to the operator Owhen the repressor binds to tryptophan when the repressor binds to the inducer

Gray seed color in peas is dominant to white Assume that Mendel conducted a series of experiments where plants with gray seeds were crossed among themselves and the following progeny were produced 302 gray and 98 white What is the most probable genotype of each parent Gg x Gg ggx Gg GG x Gg GG gg

The genetic code is redundant What is meant by this statement A single codon can specify the addition of more than one amino acid More than one codon can specify the addition of the same amino acid The genetic code is different for different domains of organisms The genetic code is universal the same for all organisms

4 Next kinetic studies were carried out with the enzymes A plot of velocity vs phenylalanine concentration yields a sigmoidally shaped curve What does this tell you about the enzyme

5 Kinetic data in which PAH activity is compared with and without preincubation with phenylalanine is shown in Figure 30 3 Give a structural basis for the interpretation of these data

H N CH 01 phenylalanine CH phenylpyruvate 02 tissue protein phenylalanine hydroxylase H 0 BHA NADH H dietary protein NAD melanin epinephrine H N CH Phenylketonuria tyrosine CH OH thyroxine p hydroxyphenylpyruvate homogentisate maleylacetoacetate fumarylacetoacetate fumarate acetoacetate 10 The cause for the mental retardation associated with untreated PKU is not completely understood but it is believed to arise from the high concentration of phenylpyruvate which is a product of a transamination reaction with phenylalanine and a ketoglutarate The phenylpyruvate is believed to be toxic to the developing brain Write the balanced equation for the transamination of phenylalanine to phenylpyruvate and include the structures of the reactants and products Identify any cofactors needed

10 The cause for the mental retardation associated with untreated PKU is not completely understood but it is believed to arise from the high concentration of phenylpyruvate which is a product of a transamination reaction with phenylalanine and a ketoglutarate The phenylpyruvate is believed to be toxic to the developing brain Write the balanced equation for the transamination of phenylalanine to phenylpyruvate and include the structures of the reactants and products Identify any cofactors needed to accomplish the reaction

Which of the following mechanisms is used to coordinate the expression of multiple related genes in eukaryotic cells OA given gene may have multiple enhancers but each enhancer is generally associated with only that gene and no other Environmental signals enter the cell and bind directly to promoters The genes are organized into a large operon allowing them to be coordinately controlled as a single unit A single repressor is able to turn off several related genes

A couple has a child with Down syndrome The mother is 39 years old at the time of delivery Which of the following is the most probable cause of the child s condition One member of the couple underwent nondisjunction in somatic cell production The mother had a chromosomal duplication The woman inherited this tendency from her parents One of the gametes in the mother most likely underwent nondisjunction during meiosis

Which of the following effects might be caused by reduced or very little active telomerase activity Cells may become cancerous Cells maintain normal functioning Telomere lengthens in germ cells Cells age and begin to lose function

Listen What type of synovial joint is labeled as 6 and what is its range of motion 1 3 5 P inint Nonaxial 2 4 6

What structure is labeled as 1 5 7 8 Postsynaptic membrane T tubule Presynaptic membrane Acetylcholine receptor Potassium Acetylcholinesterase Axon terminal Synaptic vesicle Calcium Synaptic cleft Sodium Acetylcholine 6030 2 6 10 11 4 12

A motor unit is A a group of linked muscle cells OB a period of time during muscle contraction C all the axons of nerve cells that innervate a muscle D a single motor neuron and all the muscle cells it innervates

A superficial muscle of the leg this one dorsiflexes the foot OA fibularis longus B gastrocnemius C soleus D tibialis anterior

8 Patients with the disease PKU tend to have blue eyes fair hair and very light skin Explain why

More than 60 different mutant PAH genes have been identified in PKU patients State in general what effect the following changes in the DNA would have on the resulting protein Be specific I

Which kinds of synovial joints can move in two and only two planes of the body A condyloid B ball and socket OC hinge D pivot AAAAA

Each of the elements that make up a skeletal muscle is surrounded by connective tissue Which words below correctly pair the connective tissue layer with the corresponding muscle structure A entire muscle epimysium B functional group of muscles endomysium C fascicle perimysium D muscle fiber deep fascia

A neuron and all the muscle fibers it stimulates is called a A myoneural junction B synaptic cleft C fascicle D motor unit

At the neuromuscular junction the electrical signal of the nerve A is sent directly to muscle B causes the axon terminal to release Na and K OC causes the axon terminal to release acetylcholine ACh D stimulates formation of the neurotransmitter acetylcholine ACh

The structural classification of joints is based on OA the location of the joint in the axial skeleton B the type of connective tissue between the articulating bones C the amount of movement permitted at the joint D the shape of the articulating bones

An aponeurosis is A a disease of the neuromuscular junction B a structural part of the interior of muscle cells OC a covering of the myoneural region D similar to a tendon in function

The function of the neuromuscular junction is to OA connect sensory neurons directly to muscle B stimulate or inhibit the activity of skeletal muscles OC convey a signal from the nervous system to skeletal muscle D link nerve endings to muscle to protect the nerve structurally

What is true about the movement properties of the following joints OA Some synovial joints are freely movable others are immovable B Cartilaginous joints are freely movable C All synovial joints are freely movable D Fibrous joints permit no movement

Which of these joints moves in only two planes A hip B metacarpophalangeal C elbow D shoulder

This bone is commonly called the kneecap OA patella OB pelvic OC petrous D pectoral

These bones form the pectoral girdle A femur and coxal bone OB humerus and scapula C clavicle and scapula D coxal bones

muscle cells consist of branched uninucleate cells with junctions called intercalated discs 4 A Smooth B Connective C Cardiac D Skeletal

Skin color can indicate certain disease states A reddened flushed face might indicate A liver disease B Addison s disease C hypertension fever or embarrassment D poor oxygen in the blood due to lung disease

This layer of the dermis is responsible for fingerprints A areolar layer B deep stratum basale OC papillary layer D reticular layer

From deep to superficial the layers of the epidermis of thin skin are A stratum corneum stratum granulosum stratum spinosum stratum basale B stratum spinosum stratum basale stratum corneum stratum granulosum stratum basale stratum spinosum stratum granulosum stratum corneum D stratum granulosum stratum spinosum stratum corneum stratum hacalo

This accessory organ of the skin is composed primarily of dead keratinized cells A eccrine gland B apocrine gland C hair D sebaceous gland

Which muscle tissue type is controlled voluntarily A cardiac and smooth B smooth C cardiac OD skeletal

Epithelial cells are specialized to A protect support and bind together other tissues B receive stimuli and conduct electrical signals to all parts of the body C secrete filter and absorb D actively contract

What is not true of connective tissue A Its matrix contains fibers B Its matrix is produced by the cells within the tissue C It contains both cells and noncellular nonliving material D All connective tissues contain elastic fibers

Which muscle is highlighted pronator teres flexor carpi radialis extensor carpi radialis brevis flexor digitorum superficialis Submit Request Answer LT VA 16 Life Size Muscle Torso 27 port 38 Scientific

On to which structure does the highlighted muscle insert Omedial epicondyle of ulna olecranon process of ulna LT M11 Deluxe Muscular Arm 6 part 3B Scientific head of radius

On to what common structure do both heads of the highlighted muscle insert O radial tuberosity of radius Ostyloid process of radius olecranon process of ulna lateral epicondyle of ulna LT M11 Deluxe Muscular Arm 6 part 3B Scientific Submit Request Answer

Which muscle is highlighted pronator teres supinator flexor digitorum profundus extensor digitorum Submit Request Answer LT M11 Deluxe Muscular Arm 6 part 3B Scientific

Which muscle is highlighted brachialis biceps brachii triceps brachii long head triceps brachii medial head Submit Request Answer LT M11 Deluxe Muscular Arm 6 part 3B Scientific P Pe

What is an action of the highlighted muscle extension hand at wrist abduction of thumb flexion of hand at wrist adduction of hand LT VA 16 Life Size Muscle Torso 27 part 38 Scientific

Which muscle is highlighted flexor carpi ulnaris extensor digiti minimi extensor carpi ulnaris anconeus LT VA 16 Life Size Muscle Torso 27 part 3B Scientific

medial knee Anterior left thigh Which structure is indicated by the arrow tensor fasciae latae lateral Ogracilis Oiliotibial tract

Which muscle is highlighted Opsoas major O pectineus Oiliacus copyright by somso 2010 www

Which muscle is highlighted fibularis longus soleus fibularis tertius tibialis anterior LT VA 16 Life Size Muscle Torso 27 part 38 Scientific PPE

Which muscle is highlighted semitendinosus Osemimembranosus gluteus medius Ogracilis copyright by somse 2010 www someo com P Pearson right 2023 Pearson Education Inc All rights reserved Terms of Use